There are a number of patents for digital scales. Current scales generally employ sensing devices such as transducer load cell assemblies or piezoelectric sensors for measuring the weight, an analog to digital converter for converting the sensed signal into digital format, and a microcomputer for receiving the A/D converted data and displaying the digital representation onto a digital display, such as an LCD display. Scales of this type are generally known both as regards their construction and their operation, so that a detailed description can be eliminated.
Typically, with an electronic scale, an object is positioned on a weighing platform, where the weight of the object causes the weighing platform to move downward. The downward force causes the weighing platform to exert a force or pressure on a transducer. The transducer converts the downward force into an analog signal in terms of a voltage or a current having a magnitude, which varies according to the weight of the object.
This analog signal is easily converted for digital display purposes with the use of an analog to digital converter (A/D converter). Essentially, the prior art shows many techniques for performing analog to digital conversion. Primarily, the object of such devices is to respond to an analog signal to provide therefrom a digital code or a digital signal, which can be processed by conventional digital circuitry to eventually activate a digital display, such that, the weight of the object is displayed on the display screen.
When a scale reaches or exceeds its maximum capacity, an overload condition occurs which can produce inaccurate results and, more importantly, damage the scale. Accordingly, there is a need in the art for a means to warn of a potential overload condition for a scale.